Achieving highly efficient hierarchical photocatalysts for hydrogen evolution is always challenging. Herein, hierarchical mesoporous NiO@N‐doped carbon microspheres (HNINC) are successfully fabricated with ultrathin nanosheet subunits as high‐performance photocatalysts for hydrogen evolution. The unique architecture of N‐doped carbon layers and hierarchical mesoporous structures from HNINC could effectively facilitate the separation and transfer of photo‐induced electron–hole pairs and afford rich active sites for photocatalytic reactions, leading to a significantly higher H2 production rate than NiO deposited with platinum. Density functional theory calculations reveal that the migration path of the photo‐generated electron transfer is from Ni 3d and O 2p hybrid states of NiO to the C 2p state of graphite, while the photo‐generated holes locate at Ni 4s and Ni 4p hybrid states of NiO, which is beneficial to improve the separation of photo‐generated electron–hole pairs. Gibbs free energy of the intermediate state for hydrogen evolution reaction is calculated to provide a fundamental understanding of the high H2 production rate of HNINC. This research sheds light on developing novel photocatalysts for efficient hydrogen evolution.

Catalysts based on metallic NPs have shown high activities in heterogeneous catalysis, due to their high fractions of surface-active atoms, which, however, will lead to the sacrifices in stability and recycle of catalysts. In order to balance well the relationship between activity, stability, and recovery, in this paper, we have constructed a 3D mesoporous sphere structure assembled by N-doped carbon coated Ni/Pd NP heterojunctions (Ni/Pd@N–C). This obtained Ni/Pd@N–C has shown high catalytic activity, durability and recyclability for the hydrolytic dehydrogenation of ammonia borane (AB). Further investigations, including experimental and theoretical results, have shown that the unique structural features, the synergistic effect between Ni and Pd, and the coating of N-doped carbon layer are responsible for the good catalytic performance of Ni/Pd@N–C mesoporous spheres.

Improving the separation efficiency of photogenerated carriers and exposing more active sites are two important factors to improve photocatalytic efficiency of photocatalyst. Designing appropriate materials with special structure and composition...